A three-phase star-connected alternator working at 1800 KVA,50 Hz,2100 V, has an armature dc resistance of 0.15 Q. Assume the ac resistance is 1.5 times the dc resistance. A field current of 65 A produces a short circuit current of 37O A and for the same field current the open circuit voltage is 1000 V. Determine a} Synchronous reactance of the machine b) Full load regulation at 0.7 leading c) Power angle a)

A three-phase star-connected alternator working at 1800 KVA,50 Hz,2100 V, has an armature dc resistance of 0.15 Q. Assume the ac resistance is 1.5 times the dc resistance. A field current of 65 A produces a short circuit current of 37O A and for the same field current the open circuit voltage is 1000 V. Determine a} Synchronous reactance of the machine b) Full load regulation at 0.7 leading c) Power angle a)

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

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